Weird behavior of Files app observed, when folder shared with User B

Steps:
1. On User B, goto Files> Shared with me folder.
2. There are 3 folders shared with User B. One of the folder named 'File Browser Assets' is added to My drive from web drive (drive.google.com)
3. Click on either of the shared folders (pics/TestSave) and hit back space. (Please refer the video).
4. "Chrome Syncable FileSystem" folder is created which in turn contains some junk folders.
5. Also observe that files from pics/TestSave are now exposed outside their respective folders. 
6. Once again go to Shared with me folder in Files. 
7. Now, "Chrome Syncable FileSystem" folder disappears.  
8. Once again the shared folders (pics, TestSave) are empty. The exposed files are also vanished. 

Here is the video link for this issue:
https://pantheon.corp.google.com/storage/browser/chromiumos-test-logs/bugfiles/cr/769015/

fukino@ - Would you be able to take a look at this one?

I examined and found the issue in Comment #1 is an independent bug. Filed  Issue 808937 .

<files-triage>

Oops - changing back to Started.

Hi mkarkada@,

Is the issue described in the bug description (not in comment #) still reproducible?
I was not able to reproduce it on ToT.

Do you remember the sizes of files under shared directory?
If they are big, uploading them can take a while, it can cause the delay of displaying files in user B.

Hi fukino,
The issue in the bug description is not reproducible where the shared folder shows empty. But, it does happen that few shared files goes missing from the shared directory and some files/folder gets exposed outside the shared directory.

Referring the issue video attached in this comment:
Shared folder named 'Audio' should contain 10 files in it but only 8 files appear in this shared folder. Meaning 2 files are missing.

The size of entire shared folder was around 4.6 GB and size of 'Audio' folder was around 12 MB.
Issue video:
https://pantheon.corp.google.com/storage/browser/chromiumos-test-logs/bugfiles/cr/769015/10421.0.0-66.0.3344.0/

To add on, the issue in comment #1 is 100% reproducible.
Tested on CrOS version: 10421.0.0, 66.0.3344.0 cave and caroline devices.

Moving to M-67, please update if incorrect.

Fukino-san - as this is marked P-1 for M-67, do you think you'll be able to finish this in time? Are you still working on this?

The issue in the bug description is not reproducible according to comment #12.
The issue described in #12 (Missing entries in shared folder) can happen when the shared folder is bug and syncing files take time.

I'll focus on the issue described in #1: "Chrome Syncable FileSystem" is displayed in "Shared with me" folder.
I was able to reproduce the issue, and working on a fix for it.

WIP CL for the issue in c#1: https://crrev.com/c/984832

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/d547564a99138d3861afef3e6540f0733efef728

commit d547564a99138d3861afef3e6540f0733efef728
Author: Naoki Fukino <fukino@chromium.org>
Date: Thu Mar 29 01:08:27 2018

Files app: Go to parent folder on BACKSPACE based on the current breadcrumbs.

On BACKSPACE, users should be navigated to the parent folder of the current one.
We have used Entry.getParent() to identify the parent folder, but it is not safe
when the current folder is under fake directories.
As we already have the current folder's ascendant folders as breadcrumbs, using
it to identify parent folders is safe for consistency between UI and
shortcut-key handling.

Bug:  769015 
Test: Manually tested
Cq-Include-Trybots: master.tryserver.chromium.linux:closure_compilation
Change-Id: Id3af343dd12921fb14d37f2bed6ce146a478987a
Reviewed-on: https://chromium-review.googlesource.com/984832
Reviewed-by: Sasha Morrissey <sashab@chromium.org>
Commit-Queue: Naoki Fukino <fukino@chromium.org>
Cr-Commit-Position: refs/heads/master@{#546687}
[modify] https://crrev.com/d547564a99138d3861afef3e6540f0733efef728/ui/file_manager/file_manager/foreground/js/main_window_component.js
[modify] https://crrev.com/d547564a99138d3861afef3e6540f0733efef728/ui/file_manager/file_manager/foreground/js/ui/location_line.js

Marking as Fixed.
Please verify if the issue described in comment #1 is fixed.